Subscription for a single topic works successfully but when I try to subscribe to another topic, i get the the exception below :-

com.salesforce.emp.connector.CannotSubscribe: Unable to subscribe to [/topic/13q8_3zpqi_j7akbccq:-1] [https://ap4.salesforce.com/cometd/39.0] : 403:denied_by_security_policy:create_denied
	at com.salesforce.emp.connector.EmpConnector.lambda$subscribe$6(EmpConnector.java:378)

I am confused here why it is not allowing me to subscribe since I only have 11 topics in my developer salesforce account, subscribed to one of them and trying to subscribe to another. As per the documentation, maximum 20 subscriptions are allowed per topic.

Strangley I am not able to reprodcue this issue on a standalone Java application which I wrote for POC purpose. This exeption occurs only when I integrate it with a java based web application.